import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { CharacterEquipment } from '../equipment/entities/character-equipment.entity';
import { CharacterItem } from '../items/entities/character-item.entity';
import { EquipmentSlot } from '../items/equipment-slot.enum';
import { ItemRarity } from '../items/item-rarity.enum';

export interface InventoryItemDto {
  id: string;
  quantity: number;
  equipped: boolean;
  item: {
    key: string;
    name: string;
    description: string;
    rarity: ItemRarity;
    equipmentSlot: EquipmentSlot | null;
    weaponDamage: number;
    bonusAttack: number;
    bonusHp: number;
    bonusArmor: number;
    iconPath: string;
  };
}

export interface InventoryResponseDto {
  items: InventoryItemDto[];
}

@Injectable()
export class InventoryService {
  constructor(
    @InjectRepository(CharacterItem)
    private readonly characterItems: Repository<CharacterItem>,
    @InjectRepository(CharacterEquipment)
    private readonly equipment: Repository<CharacterEquipment>,
  ) {}

  async getInventory(characterId: string): Promise<InventoryResponseDto> {
    const [items, equipped] = await Promise.all([
      this.characterItems.find({
        where: { characterId },
        relations: { itemDefinition: true },
        order: { createdAt: 'ASC' },
      }),
      this.equipment.find({ where: { characterId } }),
    ]);
    const equippedIds = new Set(equipped.map((row) => row.characterItemId));

    return {
      items: items.map((characterItem) => ({
        id: characterItem.id,
        quantity: characterItem.quantity,
        equipped: equippedIds.has(characterItem.id),
        item: {
          key: characterItem.itemDefinition.key,
          name: characterItem.itemDefinition.name,
          description: characterItem.itemDefinition.description,
          rarity: characterItem.itemDefinition.rarity,
          equipmentSlot: characterItem.itemDefinition.equipmentSlot,
          weaponDamage: characterItem.itemDefinition.weaponDamage,
          bonusAttack: characterItem.itemDefinition.bonusAttack,
          bonusHp: characterItem.itemDefinition.bonusHp,
          bonusArmor: characterItem.itemDefinition.bonusArmor,
          iconPath: characterItem.itemDefinition.iconPath,
        },
      })),
    };
  }
}